1. Field of the Invention
The subject invention relates to firearms, to firearm aiming assistance technology, and to laser systems and, more specifically, to firearms equipped with devices for providing an aiming mark on a target, to methods and apparatus for assisting the aiming of a firearm, and in particular to methods and apparatus for assisting the aiming of a firearm with a light beam from a laser.
2. Disclosure Statement
This disclosure statement is made pursuant to the duty of disclosure imposed by law and formulated in 37 CFR 1.56(a). No representation is hereby made that information thus disclosed in fact constitutes prior art, inasmuch as 37 CFR 1.56(a) relies on a materiality concept which depends on uncertain and inevitably subjective elements of substantial likelihood and reasonableness, and inasmuch as a growing attitude appears to require citation of material which might lead to a discovery of pertinent material.
For over seventy years, proposals have been made for assisting the aiming of firearms with light beams or light spots on targets. Reference may, for instance be had to U.S. Pat. No. 894,306, which proposes clamping of an elongate light source, including a small electric incandescent lamp and a projection lens, to the barrel of a handgun, U.S. Pat. No. 1,452,651, which proposes clamping of a flashlight to a handgun barrel, U.S. Pat. Nos. 1,826,004 and 2,844,710 which propose clamping of an electric incandescent lamp and battery unit to a handgun, aand U.S. Pat. Nos. 3,010,019 and 3,974,585 which also propose employment of electric incandescent lamps for providing aiming marks on firearm targets or on an optical sight.
Practical limitations on light output intensity and coherence achievable with incandescent lamps have relegated the utility of such proposals to nightsight or target finder equipment of rather limited range.
Aim assistance electric incandescent lamps also have found a limited application in reticle image projectors of complex computing sights, as may be seen from U.S. Pat. Nos. 2,660,794 and 2,693,031. Apart from such special applications, the use of electric incandescent light aiming assists for firearms appears to have become restricted to aim assessment apparatus, as seen in U.S. Pat. No. 3,508,833.
Further proposals were spawned by the development of laser diodes comparable in size and ruggedness to small incandescent light bulbs (see U.S. Pat. No. 3,867,764). The utility of laser diodes as aiming devices was, however, generally limited to marksmanship trainer, boresight alignment, weapon simulator and similar applications, as may, for instance, be seen from U.S. Pat. Nos. 3,633,285, 3,782,832, 3,898,747, 3,938,262 and 3,995,376.
The success of gas discharge lasers in the surveying instrument field illustrated, for instance, by U.S. Pat. Nos. 3,533,700, 3,619,069, 3,667,849, 3,796,496 and 3,823,313, similarly spawned proposals to use that type of laser in weapon aiming systems. As apparent from U.S. Pat. No. 4,026,054, an early proposal of this type structured a laser aiming system in the manner of firearm telescope sights, seen, for instance, in U.S. Pat. Nos. 870,272, 1,641,019, 2,510,289, 2,597,466 and 3,153,856, and also in French Pat. No. 492,773 by Albert Amigues and Louis Huet, issued 2 Apr. 1919.
In the course of this development spanning seven decades, there has been a continuous quest for the best method of activating the aiming assistance or sighting appliance at the most appropriate moment in the operation of the firearm. In this context, the above mentioned U.S. Pat. No. 894,306 provided an electric switch controlled by a manually actuable button at the back of the revolver stock or handle. In practice, this required the operator to contiously actuate the switch in a manner separate from the operation of the firearm, thereby occupying or even detracting the operator's attention. In principle, the proposals according to the above mentioned U.S. Pat. Nos. 1,452,651, 1,826,004, 3,974,585 and 4,026,054, which provide actuating switch means on or at the sighting appliance or its power supply, are afflicted with the same kind of disadvantage.
Another proposal, disclosed in the above mentioned U.S. Pat. No. 2,844,710, attempted to alleviate this problem by equipping the finger trigger of a firearm with a spring carrier having an electric switch contact attached thereto and standing normally insulated from the trigger but in juxtaposition to its finger grip. In the use of that firearm, pressure on the spring carrier closed an electric circuit through its contact and trigger, to energize an electric bulb for projection of a spot of light in the direction in which the firearm was aimed at the time. While such a construction may have seemed to provide an activation mechanism that is convenient to operate by the marksman, it is noted that the proposed spring carrier just mentioned constitutes in effect a foreign object on the finger trigger, is subject to being bent out of shape and is easily dislodged during handling and operation of the firearm. Also, that proposal according to the mentioned U.S. Pat. No. 2,844,710 does not appear to disclose any positive safeguard against accidental firing of the weapon by a marksman who merely wants to test the operation of the aiming device or draw a bead on a target, such as for warning purposes, without wanting to fire a shot.
Out of these concerns and similar considerations, use of finger trigger switches has become relegated to the toy pistol field and to weapon fire simulation systems, in which light beams are protected from a toy pistol or simulated weapon upon actuation of the finger trigger to photocells on a target, as may be seen from the above mentioned U.S. Pat. Nos. 3,294,401, 3,898,747 and 3,995,376.
This, of course, is akin to proposals which employ a trigger-actuated switch for connecting a light detector in a simulated weapon to an indicator for aim assessment or scoring purposes, as proposed in the above mentioned U.S. Pat. Nos. 3,508,833 and 3,904,204. In principle, such proposals are in effect only an extension of marksmanship training and weapon simulators which use the acoustical energy developed by the firearm mechanism, as proposed in the above mentioned U.S. Pat. No. 3,633,285 or a piezoelectrically transduced mechanical energy from a rifle's hammer as proposed in the above mentioned U.S. Pat. No. 3,938,262, for the purpose of simulating the firing of a shot by the emission of a laser beam.
Against this background, the above mentioned recent U.S. Pat. No. 4,079,534 proposes the assembly of the sighting apparatus and its power supply in a separate unit which is attachable to the firearm as desired. According to that proposal, a special trigger mechanism, separate and distinct from the trigger mechanism of the firearm, has its own separate finger grip disposed adjacent the finger grip of the firearm, for operating a switch mechanism on a shockproof mount for activating the light emitting device. Thus when it is desired to activate the light emitting device to project a beam of coherent light onto a target that is to be fired upon, movement of the special finger grip of the separate trigger mechanism will cause closing of the switch contacts that supply current to the light emitting device; the express purpose of this prior-art design being to project a beam onto the target when the marksman is ready to fire a round.
In practice, however, there is frequently a need to warn a supposed criminal or wrongdoer, hopefully with the result of avoiding a shooting confrontation. Laser beam aiming devices capable of providing a vivid light spot that cannot fail to impress even a seasoned criminal, tend to have such a preventive effect that danger to life and limb can be avoided. Of course, this presupposes that the police officer or similar law enforcement personnel can be sure that his firearm will not go off when he trains the aiming device on a suspect. No teaching appears from the latter prior-art proposal that such assurance is implicit in the proposed dual finger grip arrangement. Also, a dual finger grip and trigger mechanism arrangement tends to duplicate bulk, costs and maintenance requirements of the firearm and laser aiming device combination.
Especially in police and law enforcement work, bulk and frangibility are particularly detrimental factors in the fight against crime, where weapons often become clubs in hand-to-hand combat or other tight situations.
Laser aiming devices should thus in practice be as compact and rugged as the firearm itself, in order to be of genuine practical use and desired reliability. This also applies to the power supply, including the portable power source and its combination with the firearm. Despite a history spanning some seven decades, the prior art apparently has not been capable of evolving a viable solution in this respect.
In particular, the above mentioned U.S. Pat. No. 894,306 simply proposes a relative large cylindrical battery to be screwed into the butt of the firearm at a threaded terminal portion, whereby the cylindrical battery body simply hangs down from the stock of the weapon. It is not seen how such a combination could be useful for law enforcement purposes or would even be suitable for private use. The same comment appears applicable to the proposals according to which batteries are located in the sighting equipment itself, as shown, for instance, in the above mentioned U.S. Pat. Nos. 1,452,651, 1,826,004 and 2,844,710.
Even though the last twenty years have seen substantial increases in battery power capacity, proposals to accommodate a battery in the handgrip have been limited to the target game field, such as in the above mentioned U.S. Pat. No. 3,294,401, where such a battery energizes a flash tube in a toy gun for illuminating photocell targets, and to the marksman training field, where a battery in the stock of a weapon energizes a small solid state laser device for training purposes, as apparent from the above mentioned U.S. Pat. No. 3,995,376. Particularly the low power consumption of laser diodes and similar solid-state devices permits accommodation of the requisite low-energy batteries in the laser transmitter assembly, aiming light adapter or simulated firearm structure itself. However, such designs using only laser diodes are generally relegated in their utility to the marksmanship training and weapon fire simulation fields, as appears from the above mentioned U.S. Pat. Nos. 3,633,285, 3,867,764 and 3,898,747.
For applications involving actual firearms with relatively powerful laser aiming assistance devices, separate box-like power supplies attached to the side of the firearm externally thereof, either directly or through the intermediary of an attachment assembly, have been evolved by more recent prior-art endeavor, as may be seen from the above mentioned U.S. Pat. Nos. 4,026,054 and 4,079,534.
This, of course, adds to the bulk of the weapon system and detracts from its ruggedness and to some extent also from its smooth operation.